Computer software applications today provide a wide variety of controls that allow users to perform even relatively complex manipulations of content. For example, the field of graphics processing applications, including image-processing packages, has broadened and matured to a point where many image processing programs and tools permit a user to selectively adjust an array of image characteristics. Broadly speaking, many of these image-editing tasks revolve around altering the color composition of a digital photograph or other image, or the exposure or lighting characteristics of the subject image or file. Within each category of task, commercially available programs typically offer the user a number of tools that can be activated by sliders, graphs or other interface objects. For instance, image processing packages exist which permit a user to change the relative amounts of red, green or blue (RGB) components or cyan, magenta, yellow or black (CMYK) component colors in the pixels of an image, for instance by sliding those buttons to the left or right.
However, providing a user control over complex manipulations of content presents various difficulties or compromises. For one, software applications today do not include acceptable means for implementing user-altered parameters. For example, with respect to digital image manipulation, an arbitrary curve may be generated by a user's alterations of light and exposure parameters. Presently, software applications are unable to correctly approximate such an arbitrary curve and, thus, the usefulness of the control set is compromised. Moreover, performing a sequence of tasks to achieve a desired overall effect on a piece of content may require that the user learn an extensive set of skills in that particular application, remember the sequence which they have performed and be able to informally predict the results of the next step or editing option. Users may not therefore be able to be as productive in carrying out those time-consuming manual tasks, and the results may still not conform to the user's intended editing objectives.